I have an unused toilet in my circa 1964 homes basement that I would like to remove, but rather than capping it off I would like to convert the toilet drain into a basement floor drain. Is this possible, and if so, what is required, and how is it done?

Water traps to prevent sewer gas are built into toilets, so you won't find one when you remove the toilet. Plus there's the added danger o sewage itself, and that's the first place it will backup. See what the drain pipe is made of. Put a PVC plug in it (with a rubber/hose clamp fitting). Open it when needed.

Somewhat difficult at this point but can be done. There is no trap on the existing line, the toilet water level acts as a trap. You would have to remove enough concrete sideways and depth, so you could attach a floor trap body into the existing stub using a reducer. You will need to find out from your local inspectors what type of system you can install as there are a couple of different types, some may not be approved. Many authorities require trap primers in lieu of deep-seal P-traps where floor drains are used infrequently so they don't dry out. In that case, you will need to run a water line too. Once everything is hooked up, slope the concrete back to the drain so water will flow into it. As I said, not easy at this point.

While the other two answers are correct, there is still a solution. You can install a floor drain and keep within all codes. The best recommendation I can offer is to install a jr smith Fig. 2530 or equal which includes a trap for shallow install and contains a backwater mechanism built in to prevent any sanitary back-ups. I hope this helps.